HTTP status codes

100

Continue

This interim response indicates that the client should continue the request or ignore the response if the request is already finished.

101

Switching Protocols

This code is sent in response to an Upgrade request header from the client and indicates the protocol the server is switching to.

102

Processing

This code indicates that the server has received and is processing the request, but no response is available yet.

103

Early Hints

This status code is primarily intended to be used with the Link header, letting the user agent start preloading resources while the server prepares a response or preconnect to an origin from which the page will need resources.

104-199

Unassigned

200

OK

Depending on the HTTP method: GET: The resource has been fetched and transmitted in the message body. HEAD: The representation headers are included in the response without any message body. PUT or POST: The resource describing the result of the action is transmitted in the message body. TRACE: The message body contains the request message as received by the server.

201

Created

The request succeeded, and a new resource was created as a result. This is typically the response sent after POST requests, or some PUT requests.

202

Accepted

The request has been received but remains unprocessed, reflecting a noncommittal status since HTTP does not allow for asynchronous responses to indicate the request's outcome. This status is designed for situations where another process or server manages the request, or for batch processing scenarios.

203

Non-Authoritative Information

This response code indicates that the returned metadata differs slightly from what is available on the origin server, as it has been sourced from a local or third-party copy. It is primarily used for mirrors or backups of other resources; otherwise, the 200 OK response is generally preferred over this status.

204

No Content

There is no content to send for this request, but the headers may provide useful information. The user agent may update its cached headers for this resource with the new ones provided.

205

Reset Content

Tells the user agent to reset the document which sent this request.

206

Partial Content

This response code is utilized when the client sends a Range header to request only a portion of a resource.

207

Multi-Status

Conveys information about multiple resources, for situations where multiple status codes might be appropriate.

208

Already Reported

Used inside a <dav:propstat> response element to avoid repeatedly enumerating the internal members of multiple bindings to the same collection.

209-225

Unassigned

226

IM Used

The server has successfully fulfilled a GET request for the resource, and the response represents the result of one or more instance manipulations applied to the current instance.

227-299

Unassigned

300

Multiple Choices

The request has multiple possible responses, and the user agent or user should select one of them. While there is no standardized method for making this selection, it is recommended to provide HTML links to the available options so the user can choose.

301

Moved Permanently

The URL of the requested resource has been changed permanently. The new URL is given in the response.

302

Found

The URI of the requested resource has been temporarily changed, with the possibility of further changes in the future. As a result, the client should continue to use the same URI for future requests.

303

See Other

The server sent this response to direct the client to get the requested resource at another URI with a GET request.

304

Not Modified

This is used for caching purposes, informing the client that the response has not been modified, allowing the client to continue using the same cached version of the response.

305

Use Proxy

The status code was defined in a previous version of the specification and is now deprecated.

306

(Unused)

Originally defined in an earlier version of the HTTP specification, this status indicated that a requested response must be accessed through a proxy. It has been deprecated due to security concerns related to the in-band configuration of proxies.

307

Temporary Redirect

The server sends this response to direct the client to get the requested resource at another URI with the same method that was used in the prior request. This has the same semantics as the 302 Found HTTP response code, with the exception that the user agent must not change the HTTP method used: if a POST was used in the first request, a POST must be used in the second request.

308

Permanent Redirect

The permanent redirect status code indicates that the target resource has been assigned a new permanent URI and any future references to this resource ought to use one of the enclosed URIs.

309-399

Unassigned

400

Bad Request

The server cannot or will not process the request because it is perceived as a client error, such as malformed request syntax, invalid request message framing, or deceptive request routing.

401

Unauthorized

While the HTTP standard specifies "unauthorized," this response semantically means "unauthenticated," indicating that the client must authenticate itself to receive the requested response.

402

Payment Required

This response code is reserved for future use. Originally intended for digital payment systems, it is rarely utilized, and no standard convention currently exists for its application.

403

Forbidden

The client lacks access rights to the content, meaning it is unauthorized, and the server is refusing to provide the requested resource. Unlike the 401 Unauthorized status, the server is aware of the client's identity.

404

Not Found

The server cannot find the requested resource. In a browser, this indicates that the URL is unrecognized, while in an API, it may signify that the endpoint is valid but the specific resource does not exist. Servers may also use this response instead of a 403 Forbidden to conceal the existence of a resource from unauthorized clients. This response code is likely the most well-known due to its frequent appearance on the web.

405

Method Not Allowed

The request method is recognized by the server but is not supported by the target resource. For instance, an API may not permit the use of DELETE to remove a resource.

406

Not Acceptable

This response is sent when the web server, after conducting server-driven content negotiation, fails to find any content that meets the criteria specified by the user agent.

407

Proxy Authentication Required

This is similar to 401 Unauthorized but authentication is needed to be done by a proxy.

408

Request Timeout

This response is sent by some servers on an idle connection, even in the absence of any prior request from the client, indicating that the server intends to close the unused connection. Some servers may simply terminate the connection without sending this message.

409

Conflict

This response is sent when a request conflicts with the current state of the server.

410

Gone

This response is sent when the requested content has been permanently deleted from the server, without any forwarding address. Clients are expected to remove their caches and links to the resource. The HTTP specification designates this status code for use with "limited-time, promotional services."

411

Length Required

Server rejected the request because the Content-Length header field is not defined and the server requires it.

412

Precondition Failed

The client has indicated preconditions in its headers which the server does not meet.

413

Content Too Large

The requested payload is larger than the limits set by the server. The server may either close the connection or return a Retry-After header field.

414

URI Too Long

The URI requested by the client exceeds the length that the server is willing to process.

415

Unsupported Media Type

The server does not support the media format of the requested data, resulting in the rejection of the request.

416

Range Not Satisfiable

The range specified by the Range header in the request can not be fulfilled, possibly because the range exceeds the size of the data for the target URI.

417

Expectation Failed

This response code indicates that the server cannot fulfill the expectation specified by the Expect request header field.

418

(Unused)

Known as the Hyper Text Coffee Pot Control Protocol (HTCPCP/1.0) which used to state that the server refuses the attempt to brew coffee with a teapot. The status code was an April 1 RFC that lampooned the various ways HTTP was abused; one such abuse was the definition of an application-specific 418 status code, which has been deployed as a joke often enough for the code to be unusable for any future use.

419-420

Unassigned

421

Misdirected Request

The request was directed to a server that is unable to generate a response. This may occur if the server is not configured to handle responses for the specific combination of scheme and authority present in the request URI.

422

Unprocessable Content

The server recognizes the content type of the request (making a 415 Unsupported Media Type status code inappropriate) and the syntax of the request content is correct; however, it was unable to process the instructions contained within.

423

Locked

The destination resource, or resource within the destination collection, was locked.

424

Failed Dependency

The request failed due to failure of a previous request.

425

Too Early

Indicates that the server is reluctant to process a request that could potentially be replayed.

426

Upgrade Required

The server refuses to fulfill the request using the current protocol but may be willing to do so if the client upgrades to a different protocol. The server includes an Upgrade header in the 426 response to specify the required protocol(s).

427

Unassigned

428

Precondition Required

The 428 status code indicates that the origin server requires the request to be conditional.

429

Too Many Requests

The 429 status code indicates that the user has sent too many requests in a given amount of time ("rate limiting")

430

Unassigned

431

Request Header Fields Too Large

The 431 status code indicates that the server is unwilling to process the request because its header fields are too large.

432-450

Unassigned

451

Unavailable For Legal Reasons

This status code indicates that the server is denying access to the resource as a consequence of a legal demand.

452-499

Unassigned

500

Internal Server Error

The server encountered an unexpected condition that prevented it from fulfilling the request.

501

Not Implemented

The server does not support the functionality necessary to fulfill the request. This response is appropriate when the server does not recognize the request method and cannot support it for any resource.

502

Bad Gateway

This error response indicates that the server, acting as a gateway to obtain a necessary response for handling the request, received an invalid response.

503

Service Unavailable

The server is currently unable to handle the request due to a temporary overload or scheduled maintenance, which will likely be alleviated after some delay.

504

Gateway Timeout

While acting as a gateway or proxy, the server did not receive a timely response from an upstream server that it needed to access to complete the request.

505

HTTP Version Not Supported

The server does not support, or refuses to support, the major version of HTTP that was used in the request message.

506

Variant Also Negotiates

The server has an internal configuration error: the chosen variant resource is configured to engage in transparent content negotiation itself, and is therefore not a proper end point in the negotiation process.

507

Insufficient Storage

The method could not be performed on the resource because the server is unable to store the representation needed to successfully complete the request.

508

Loop Detected

The server terminated an operation due to encountering an infinite loop while processing a request with "Depth: infinity." This status indicates that the entire operation has failed.

509

Unassigned

510

Not Extended (OBSOLETED)

The policy for accessing the resource has not been met in the request. The server should send back all the information necessary for the client to issue an extended request.

511

Network Authentication Required

The 511 status code indicates that the client needs to authenticate to gain network access.

512-599

Unassigned